Assessing methanotrophy and carbon fixationfor biofuel production by Methanosarcina acetivorans

Microbial Cell Factories

Research

James G. Ferry¹  Saratram Gopalakrishnan²  Hadi Nazem-Bokaee²  Costas D. Maranas²  Thomas K. Wood³ 

[1] Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 16802, University Park, PA, USA;Department of Chemical Engineering, The Pennsylvania State University, 16802, University Park, PA, USA;Department of Chemical Engineering, The Pennsylvania State University, 16802, University Park, PA, USA;Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 16802, University Park, PA, USA;

关键词: Methanosarcina acetivorans;    Genome-scale metabolic model;    Methane utilization;   

DOI  :  10.1186/s12934-015-0404-4

 received in 2015-07-15, accepted in 2015-12-22,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundMethanosarcina acetivorans is a modelarchaeon with renewed interest due to its unique reversible methane productionpathways. However, the mechanism and relevant pathways implicated in(co)utilizing novel carbon substrates in this organism are still not fullyunderstood. This paper provides a comprehensive inventory of thermodynamicallyfeasible routes for anaerobic methane oxidation, co-reactant utilization, andmaximum carbon yields of major biofuel candidates by M.acetivorans.ResultsHere, an updated genome-scale metabolic model of M. acetivorans is introduced (iMAC868 containing868 genes, 845 reactions, and 718 metabolites) by integrating information fromtwo previously reconstructed metabolic models (i.e., iVS941 and iMB745),modifying 17 reactions, adding 24 new reactions, and revising 64gene-protein-reaction associations based on newly available information. The newmodel establishes improved predictions of growth yields on native substrates andis capable of correctly predicting the knockout outcomes for 27 out of 28 genedeletion mutants. By tracing a bifurcated electron flow mechanism, the iMAC868model predicts thermodynamically feasible (co)utilization pathway of methane andbicarbonate using various terminal electron acceptors through the reversal ofthe aceticlastic pathway.ConclusionsThis effort paves the way in informing the search forthermodynamically feasible ways of (co)utilizing novel carbon substrates in thedomain Archaea.

【 授权许可】

CC BY   
© Nazem-Bokaee et al. 2016

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